This section provides background information related to the present disclosure which is not necessarily prior art.
Opposed-piston engines generally include two pistons housed within each cylinder that move in an opposed, reciprocal manner within the cylinder. In this regard, during one stage of operation the pistons are moving away from one another within the cylinder and during another stage of operation the pistons are moving towards one another within the cylinder. As the pistons move towards one another within the cylinder, they compress and, thus, cause ignition of a fuel/air mixture disposed within the cylinder. In so doing, the pistons are forced apart from one another, thereby exposing the inlet ports and the exhaust ports. Exposing the inlet ports draws air into the cylinder and this in combination with exposing the exhaust ports expels exhaust, thereby allowing the process to begin anew. When the pistons are forced apart from one another, connecting rods respectively associated with each piston transfer the linear motion of the pistons relative to and within the cylinder to one or more crankshafts associated with the connecting rods. The longitudinal forces imparted on the crankshafts cause rotation of the crankshafts which, in turn, cause rotation of wheels of a vehicle in which the engine is installed.
Generally speaking, opposed-piston engines include a bank of cylinders with each cylinder having a pair of pistons slidably disposed therein. While the engine may include any number of cylinders, the particular number of cylinders included is generally dictated by the type and/or required output of the vehicle. For example, in an automobile, fewer cylinders may be required to properly propel and provide adequate power to the vehicle when compared to a heavier vehicle such as a commercial truck, a ship, or tank. Accordingly, a light vehicle may include an engine having four (4) cylinders and eight (8) pistons while a heavier vehicle may include six (6) cylinders and twelve (12) pistons.
Such opposed piston engines have a one piece engine block (i.e. made from a single casting), that includes one cylinder bore per cylinder. The one piece engine block further includes two crankcases, one disposed to one side of the cylinder bores and the other disposed on an opposite side of the cylinder bores. A liner may be inserted into each of the cylinder bores from one of the crankcases. In order to properly accommodate and seal the liner in the one piece engine block, complicated machining in the cylinder bore is required and access to the cylinder bore is limited. This adds to manufacturing time and cost. The liner may be supported on one end to avoid rocking and to limit axial movement of the liner within the cylinder bore. For example, the liner may have an annular collar disposed at an end opposite the end of the liner that is first inserted into the cylinder bore. As such, the liner is inserted into the cylinder bore until the annular collar contacts the engine block.